Make scroll offset uncontrollable in favor of ref methods

[wuweiweiwu]

Changes based on discussion from #999.

Follow up of #1320

• scrollToCell
• clean up Grid prop mirroring
• clean up gDSFP implementations
• clean up APIs

Summary of changes:

• Grid component

  • Make Grid uncontrollable, rename scrollTop/scrollLeft props defaultScrollTop/defaultScrollLeft (only to be used on mount)
  • Limit scrollTop and scrollLeft to maximum possible values state update in scrollToPosition method(prevents issues when calling scrollToPosition multiple times with larger than max)
  • Update tests and docs

• MultiGrid component

  • Remove scrollLeft and scrollTop from state
  • Remove getDerivedStateFromProps and state handling code componentDidMount
  • Update all _onScroll methods to use scrollToPosition for syncing
  • Add scrollToPosition method (pass-thru that calls of the main scrolling grid which is _bottomRightGrid)
  • Update tests and docs

• List component

  • Make List uncontrollable, rename scrollTop to (only to be used on mount)
  • Update tests and docs

• Table component

  • Make Table uncontrollable, rename scrollTop to defaultScrollTop (only to be used on mount)
  • Update tests and docs

• ScrollSync component

  • Add flow types
  • Add registerChild to children render function parameters
  • Implement _registerChild to store refs on scrollable children
  • Call scrollToPosition on children refs in _onScroll handler sync them
  • Update tests, docs and example

• WindowScroller component

  • Update flow types
  • Rename existing registerChild method to registerChildContainer
  • Add registerChild to children render function parameters
  • Implement _registerChild to store ref on scrollable child
  • Call scrollToPosition on child ref in _handleWindowScrollEvent
    handler
  • Update tests, docs and example

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[codecov-io]

Codecov Report

Merging #1461 into master will decrease coverage by 0.26%.
The diff coverage is 95.23%.

@@            Coverage Diff             @@
##           master    #1461      +/-   ##
==========================================
- Coverage    94.7%   94.44%   -0.27%     
==========================================
  Files          47       47              
  Lines        1795     1800       +5     
==========================================
  Hits         1700     1700              
- Misses         95      100       +5

Impacted Files	Coverage Δ
source/List/List.js	78.37% <ø> (ø)	⬆️
source/Table/Table.js	90.35% <ø> (+1.75%)	⬆️
source/Grid/Grid.js	95.09% <100%> (-0.06%)	⬇️
source/WindowScroller/WindowScroller.js	92.94% <100%> (-5.8%)	⬇️
source/ScrollSync/ScrollSync.js	100% <100%> (ø)	⬆️
source/MultiGrid/MultiGrid.js	96.07% <90.47%> (-1.06%)	⬇️

---

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[somi92]

@wuweiweiwu Glad to see progress on this! Let me know if I can help.

[wuweiweiwu]

@somi92 this is thanks to all your work!!

[codecov-commenter]

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Codecov Report

Attention: Patch coverage is 95.23810% with 2 lines in your changes missing coverage. Please review.

Project coverage is 94.44%. Comparing base (489794a) to head (26d286b).
Report is 51 commits behind head on master.

Files with missing lines	Patch %	Lines
source/MultiGrid/MultiGrid.js	90.47%	2 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1461      +/-   ##
==========================================
- Coverage   94.70%   94.44%   -0.27%     
==========================================
  Files          47       47              
  Lines        1795     1800       +5     
==========================================
  Hits         1700     1700              
- Misses         95      100       +5     

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